Intake and exhaust device with multiple sections of specific geometry, for internal combustion engines

ABSTRACT

A device for optimizing the efficiency of an internal combustion engine of the type having at least one cylinder within which a piston moves. The cylinder receives an air-fuel fresh gas mixture via an intake system or channel incorporating at least one intake valve. From the cylinder, spent gas emerges and is fed to an exhaust pipe via an exhaust system or channel. The channel incorporates at least one exhaust valve. Within one of the channels where the spent gas moves, the gas passage section is adjustable so as to modify the velocity and pressure of the gas flow directed toward the cylinder and exhaust pipe.

FIELD OF THE INVENTION

This invention relates to a device applied to an internal combustionengine in accordance with the introduction to the main claim.

BACKGROUND OF THE INVENTION

As is well known, internal combustion explosion engines, particularlyfour-stroke engines, have the drawback of not achieving satisfactoryvolumetric efficiency at each engine r.p.m. because of variousphenomena, mainly the low pressure in the intake duct, the low quantityof fresh gas pushed into the cylinder, and the presence of residualspent gas therein. As a consequence, an irregular power curve isgenerated, with non-optimum power regulation.

This problem, much felt by the expert, has been confronted by providingthe engine with turbo-compressors, supplementary flap valves, variabletiming diagrams, ducts of variable length, throttle controls which openand close one and then another intake duct, megaphone exhausts, exhaustswith resonance chambers, supplementary electronically controlled exhaustvalves, etc. The results, nearly always obtained by costly andtechnically complicated arrangements, in all cases leave considerableroom for improvement. In this respect, technological progress has meantthat very high maximum power levels are reached at high r.p.m., to thedetriment of the power at low r.p.m. Moreover, and in particular, thispower is delivered irregularly and with high specific fuel consumption.

In addition to the aforesaid it must be noted that the search forimproved performance by the expert can lead to an exaggerated increasein the cross-sections of the intake and exhaust ducts, producing theopposite effect to that required. In this respect, by enlarging theseducts beyond a certain limit, the velocity of the gas column is reduced,with consequent throughput reduction.

German Patent Publication No. DE 1 914 859 describes a tubular bodysuitable to be located between the engine and the carburetor andcontaining within it an internal element which is substantially barrelshaped. At its end which is directed towards the engine, the element hasa funnel-shaped cavity wherein a conical element is located. The conicalelement's apex is directed towards the engine. According to the priorart, the known solution affects the gas flow which is directed towardsthe engine and also the flow of the gas which, already undrawn by theengine, is repelled by the piston during the first stage of its upwardmovement into the cylinder (when the intake valve is closing but isstill opened).

The known device is used along an intake channel and it is not describednor is its operation along an exhaust duct suggested. It is alwaysexternal to the exhaust duct and its use modifies the length of theintake system with the consequences which are explained below. Thisdevice does not create more than one (annular) duct portion within thetube where the barrel-shaped element is located. Hence, though itsreduces the tube's cross-section, due to its location along the path ofthe gas threads towards the engine, it operates as an-obstacle to thegas flow. In fact, the barrel-shaped element slows down the quickest gasthreads located along the longitudinal (central) axis of the tube bydeviating them against the tube wall where, due to the friction with thetube wall, they slow down. There is no dragging effect on the slowestgas threads into the gas flow towards the engine and therefore thevelocity of the flow is reduced and as a consequence the flow rate andthe filling of the cylinder are reduced.

French Patent No. 818,457 describes devices which, according to theprior art, allow a better flow of the exhaust gas towards an exhaustchannel. This prior art describes only this use (in an exhaust channel)but neither describes nor suggests the use of such devices in an intakeduct FR 818,457 describes annular elements, freely located (excepted forthe last element which is fixed) inside a channel. Each element has ajacked abutting on the channel wall and a central hole through which theexhaust gas flows.

Each of these elements restricts the channel cross-section, and alsocreates only one free section or portion wherein the gas flows.Therefore, during its path towards the exhaust the gas flow is sloweddown by the jackets of the annular bodies which negatively affects theexhaust speed of the gas from the cylinder and therefore the engineperformance.

Furthermore, the above bodies tend to cool the gas as it flows and thiscontributes to the slowing down the flow with obvious consequences onthe emptying of spent gas from the cylinder.

British Patent No. 478,575 relates to a device to expedite andfacilitate the discharge of the exhaust gases form internal combustionengines. This is obtained by arranging in the collector or chamber at ornear the transition zone from the exhaust pipe or pipes to the collectoror chamber, a series of aerofoils or slotted aerofoils, the arrangementsbeing such that the gases passing over the surface of the aerofoils athigh speed create a depression or vacuum within the collector or chamberwhich tends to draw the gases out of the exhaust pipe or pipes openinginto the collector or chamber.

In this prior art reference, the aerofoils are located outside anyexhaust pipe and is neither described nor suggested their locationinside the pipe or within an intake duct. Furthermore, the aerofoils(which are alternate solid parts) are located within a body to which theabove pipe is connected and which has a relatively large dimension. Inview of this, the known solution could never be used in a modern compactengine.

German Patent Publication No. DE 37 34 616 describes the location,within a conical body connected to an exhaust duct of a combustionengine, of a tapered element (conical body) which negatively affects thegas flow. Within the conical body, the element creates only one annularsection and is fixed to the wall of the conical body; it divides thesingle channel for the gas in a plurality of portions (creating theannular duct) which taper in the direction of the gas flow.

This known solution is not used in an exhaust duct or intake duct andhas the same drawbacks as DE 1 914 859.

OBJECTS AND SUMMARY OF THE INVENTION

An object of the invention is to provide a device for overcoming theaforesaid drawbacks.

A particular object of the invention is to provide a device whichenables an internal combustion engine volumetric efficiency to beachieved which is satisfactory at each engine r.p.m.

A further object is to provide a device which at each engine r.p.m.enables a higher power to be achieved than known engines of equaldisplacement, with lesser fuel consumption and with lesser pollutionthan these latter.

These and further objects which will be apparent to the expert of theart are attained by a device for varying the section of an induction orintake duct or of an exhaust duct of an internal combustion engine inaccordance with the accompanying claims.

By means of the device of the invention, the intake or exhaust duct isgiven a specific geometry which for equal values (given by the sum ofits cross-sections) and for equal suction or compressive forces,determines a greater gas velocity and hence a greater throughput thanknown ducts.

The consequent effects can be summarized as follows:

better air-fuel mixing;

increase in the throughput and density of the intake fresh gas charge;

increase in the expelled spent gas flow;

better volumetric efficiency at each engine r.p.m.;

increase in power;

increase in torque;

reduction in fuel consumption;

reduction in pollution.

When suitably positioned in the induction system (upstream of the intakevalve), the device of the invention, described hereinafter in detail,makes it easier for fresh gas to enter the cylinder with greater densityand velocity, so achieving greater dynamic supercharging. The consequentgreater pressure impressed on the gas column (air-fuel mixture) not onlyincreases volumetric efficiency but also opposes the “refusal”phenomenon of the fresh gas due essentially to the upward movement ofthe piston with the valve still partly open, particularly at low andmedium engine r.p.m. In this manner a permeable (“transparent”) duct isobtained for the air-fuel mixture directed towards the cylinder, and amore impermeable (braking) duct for the refusal gas which returns tothis latter.

If instead the device of the invention is positioned in the exhaustsystem, downstream of the relative valve, it enables the spent gasvelocity to be increased towards the free air, particularly after thefirst spontaneous exhaust stage, so creating greater vacuum for bettercylinder emptying, and reventing residual spent gas returning to it byknown phenomena. All this results in a higher filling coefficient ateach engine r.p.m., giving greater power, less fuel consumption and lesspollution. In this manner a more “transparent” duct is obtained for thespent gas and a more braking duct for the return gas.

The device of the invention is applicable to every type of four-strokeinternal combustion engine, with more marked effects in high-performanceengines such as those used in competitions.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will be more apparent from the accompanyingdrawing, which is provided by way of non-limiting example and on which:

FIG. 1 shows an internal combustion engine complete with induction andexhaust system with which the device of the invention is associated intwo different configurations.

FIG. 2 s hows the device of the invention applied to the feed system orto the intake duct, this figure showing the air-fuel mixture intakestage.

FIG. 3 again shows the device of the invention applied to the intakeduct during another part of the intake stage, and in which said devicedecelerates and/or halts the fresh gas repelled by the piston 1, tooppose the “refusal” phenomenon.

FIG. 4 shows the device of the invention applied to the expulsion systemor to t he exhaust duct for the spent gas, this figure showing theexhaust stage of said gas.

FIG. 5 shows the device of FIG. 4 and its action in decelerating and/orhalting the spent gas “reflected” towards the cylinder 2.

FIGS. 6—7—8—9—10—11—12—13 show some of the many implementationalconfigurations of the device of the present invention.

FIGS. 14, 14A, 15, 15A show further modifications of the invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

With reference to said figures, an internal combustion engine, offour-stroke type in the example, is indicated overall by M and comprisesone or more cylinders 2 (only one of which is shown in the figures)within which a piston 1 moves in known manner. To the cylinder 2, orrather to the engine head T provided with ducts 20 and 21 connected tothe cylinder 2, there are connected an induction duct 13 for an air-fuelmixture and an exhaust duct 12 for the spent gas expelled from thecylinder. At the cylinder head 2A there are provided valves 7 and 9(known per se) each positioned in correspondence with a respective duct13 or 12.

According to the invention, operationally associated with at least oneof the induction and exhaust ducts (ie with the duct 13 and 20 or withthe duct 21 and 12) there is positioned a device D arranged to modifythe velocity distribution of the gas flow (fresh and exhaust) within theduct, such as to make it uniform and increase the velocity of the gasflow along the wall of the relative duct, and which would be deceleratedby friction against said wall. This is achieved without reducing thethroughput of said flow, by creating within the duct a plurality ofuseful passage sections which can have various geometricalconfigurations. Modifying the useful section for the gas (fresh orexhaust) results in a variation in its transit velocity through the ductand in the pressure therein. This results in improved filling of thecylinder 2 if the device D is associated with the induction or intakeduct 13 and 20, or if said device D is associated with the exhaust duct12 and 21 it impresses a greater velocity on the gas passing through ittowards an exhaust pipe S because of a stronger vacuum generated withinsaid duct.

More specifically, with reference to FIGS. 2 and 3, these show oneembodiment of the device D of the invention operationally associatedwith the intake duct 13 (and 20). This device comprises a cylindrical orsemi-cylindrical body 25 inserted into a seat 26 formed in that duct 20of the head T connected to the exhaust duct 13. The body 25 can beformed integral with the relative seat (for example by casting), sodividing part of the duct into which it is inserted, or can beindependent of this latter and be connected to it mechanically in aremovable and interchangeable manner (with screws, bayonet coupling orthe like) or be fixed (for example by welding).

From an inner wall 25A of said body there branch one or more elements 27arranged to modify the useful passage cross-section of the combinedintake duct 13 and duct 20 (hereinafter known as the feed/intake systemor channel), so as to create section variations in the path of the freshgas fed to the cylinder. Specifically, the element or elements 27 createa plurality of ducts or sections 4 and 5 through which the fresh gaspasses before reaching the cylinder. The sections 4 and 5 can have anentry area different from their exit area. Said elements can be ofdifferent shapes and dimensions, as shown in FIGS. 6 to 13. They can besimple fins positioned with their axes incident (FIG. 6) or parallel tothe axis Z of the body 25 (and hence of the duct through which the gaspasses), or be actual variably sectioned pieces generating ducts 4 and 5of such as shape as to converge (in the direction of the gaseous flowthrough the body 25, indicated by the arrow G) towards the axis Z (FIG.9, FIG. 13) or to diverge from this axis (FIG. 13), or of variableshape, ie a first portion diverging from and a second portion convergingtowards said axis Z (FIGS. 7, 8, 10 and 11). Said elements 27 can be ofhollow conical shape with through end holes (as in FIGS. 7, 9, 13) or ofhollow conical shape but not holed (as in FIG. 12), or be solid but ofvariable section (FIGS. 10, 11), or hollow with their axis coaxial tothe axis Z but with variable wall sections (as in FIG. 8).

The device D can be positioned at any point of the path of the fresh gasfed to the engine, depending on the geometry, the displacement and hencethe type of engine M with which it is associated. Its position along thepath, ie closer to or further from the valve 7, enables different engineresponses to be obtained at different r.p.m. It can also be applied toengines operating at atmospheric pressure, or to boosted engines (withturbocompressors or positive displacement compressors), with one or morevalves positioned in the intake duct 13, so improving engine efficiency.

The use of the device D in the case of FIGS. 2 and 3 is as follows:during engine operation, the fresh gas drawn into the cylinder 2 by thepiston 1 passes through the body 25 (arrows F of FIG. 2) by way of eachsection 4 and 5 and considerably increases its velocity towards thecylinder 2, to hence generate a strong vacuum in the intake duct 13.That portion of fresh gas which stagnates or passes at low velocitythrough the induction duct 13 in proximity to the walls is drawn bymolecular friction by the effect of the vacuum generated by the fastergas column.

The flows re-compact downstream of the body 25 in the section 6 shown inFIG. 2, and on reducing their velocity transform the accumulated kineticenergy into pressure upstream of the intake valve 7, with evidentpositive effects on the filling of the cylinder 2.

At the same time, that fresh gas portion repelled by the piston 1 duringthe first stage of its upward movement, when the intake valve 7 is stillpartially open, passes through the device D in the opposite directionwithin the converging portion of the sections 4 and 5 (arrows P of FIG.3), to be decelerated and/or halted, not only by the greater pressureapplied to the gas column but also by the particular form of the deviceD.

Said gas portion is then drawn into the next cycle to mix with greateruniformity with a new fresh gas charge.

The advantages of the invention, when positioned within the inductionsystem 13, can hence be summarized as follows:

increase in the throughput and density of the indrawn fresh gas charge;

reduction in the air-fuel mixture “refusal” phenomenon at intake;

increase in engine volumetric efficiency.

Reference will now be made to FIGS. 4 and 5 which show the applicationof the device D of the invention to the spent gas exhaust duct 12. Thedevice D is totally identical to that positioned in the fresh gaspassage towards the cylinder 2 as heretofore described. Consequentlythose parts of the device identical to those already described inrelation to FIGS. 2 and 3 are indicated by the same reference numeralsand will not be further described.

In the example under examination, the device D comprises a plurality ofelements 27 in the form of fins arranged in pairs such as to divergefrom and converge towards the central axis of the duct through which thespent gas flows. Specifically, a first pair 27A of these elementsconverges (in the spent gas flow direction) towards said axis, and asecond pair 27B diverges from this axis. Between said elements there arecreated passages or sections 10 and 11 through which said gas changesits velocity, as will be indicated hereinafter. The device body 25 isassociated with the exhaust duct 12 and duct 21 of the engine head(these defining the exhaust system or channel) in the manner alreadydescribed in relation to the device D of FIGS. 2 and 3, and which willhence not be further described.

During engine operation, hot spent gas passes through the device D;after the initial stage of spontaneous gas evacuation from the cylinderconsequent on the high initial pressure on opening the exhaust valve 9,the device D causes this gas to undergo a velocity increase towards thefree air through each section 10 and 11, to hence generate a strongvacuum in the exhaust duct 12 and cylinder 2.

The residual spent gas stagnating in the cylinder and that spent gaspassing through the exhaust duct in proximity to the walls are drawn bysaid vacuum to be also pushed downstream through the exhaust duct 12towards the free air (FIG. 4, arrow K).

At the same time that spent gas which by known phenomena is “reflected”towards the cylinder 2 (arrows H of FIG. 5), this gas being detrimentalto engine efficiency, passes through the device D from downstream toupstream through the converging portions of the sections 10 and 11, tobe decelerated and/or halted by the particular form of the device.

This generates a prolongation of the spent gas extraction stage which,besides producing a more consistent emptying of the cylinder 2,facilitates its filling with fresh charge during the next cycle.

The advantages of the invention when positioned within the exhaustsystem 12 can hence be summarized as follows:

greater emptying of spent gas from the cylinder;

lesser contamination of the fresh gas charge;

greater volumetric efficiency.

From the aforegoing, the beneficial effects which the aforedescribedinvention when positioned within the intake and/or exhaust system has onthe overall engine efficiency are apparent, in that it increases engineperformance while reducing fuel consumption and atmospheric pollution.In addition, its constructional simplicity makes it extremelyeconomical, while the reliability deriving therefrom ensures a virtuallyunlimited life. In addition, its characteristics and advantages makethis device suitable for application to any suction-compression machine.

In the practical embodiment of the invention, the size, the shape, theproportioning of the feed/intake system 13, 20 and of theexpulsion/exhaust system 12, 21 (in the sense of an assembly extendingfrom the valve or valves 7-9 of the cylinder or cylinders 2 to theexternal free air through the exhaust pipe S of FIG. 1) and the locationof the elements 27 (diverging and/or parallel and/or converging and orcurved portions, etc.), can be chosen at will according to requirements.

Furthermore the body 25 of the device D can be applied in differentnumbers, shapes and positions within the feed/intake system 13, 20 fromthe entry section or sections to the intake valve or valves 7, or in theexpulsion/exhaust system 12, 21 from the exhaust valve or valves 9 tothe exit section or sections towards the free air. It can also beapplied to the vehicle dynamic intake, and to already existing engines.

FIGS. 14, 14A show a further embodiment of the invention. These figures,in which parts corresponding to those of the already described figuresare indicated by the same reference numerals, show a device D comprisingan element 27 inserted directly into the intake duct 13 or 20 (as shown)or into the exhaust duct 12 or 21. In other words, the described body 25shown in the preceding figures (for example from 6 to 13) is defined bythe duct within which the element 27 is positioned.

In the example under examination, the element 27 is shaped as a bodyconsisting of two half-cone frustums 27H and 27K, connected together attheir greater-area base 27N and tapering in opposite directions. Thebody is hollow and divides the system in which it is positioned, forexample the intake system indicated by 20, into two sections 140 and141. In the example, the system or duct 20 is cylindrical, and the totalarea of said sections 140 and 141 is constant within the duct 20. Ifthis duct should itself taper, then said area would change constantlyalong the axis (Z) of the duct.

According to the embodiment under examination, the element 27 is movable(arrows Q of FIG. 14) within the relative duct 20 along guides 142provided on the inner wall 143 of this latter. For this purpose, theelement 27 comprises end shoes 144 movable within the guides 142. Theselatter are shown rectilinear, ie parallel to said axis Z. However theycan have any orientation along the wall 143.

Moving the element 27 enables it to be positioned closer to or furtherfrom the valve (not shown) located in said duct so as to modify theconditions (velocity and pressure) of the fluid directed towards thecylinder, and hence modify the engine response to the various r.p.m. Ifthe device D is positioned in the exhaust system (for example within theduct 21) the facility for moving the element 27 towards or away from thecorresponding exhaust valve enables cylinder emptying to be improved onthe basis of engine r.p.m.

Its movement can be manual by moving the element 27 along the guides 142and then fixing it in discrete positions by screws (setscrews) 150 shownby dashed lines in FIG. 14A and operable through holes 151 providedthrough the duct 20 (or 21). Alternatively it can be moved by a suitableactuator (mechanical or hydraulic) either operated manually orpreferably controlled by a microprocessor on the basis of the enginer.p.m.

FIGS. 15 and 15A, in which parts corresponding to those of the alreadydescribed figures are indicated by the same reference numerals, show afurther embodiment of the invention in which the element 27 isassociated with an annular support body 155 to be positioned on a stepprovided at the commencement of the corresponding duct 20 or 21 (notshown) or within this latter. The embodiment shown on the figuresenables the element 27, by suitably choosing its length, to bepositioned closer to or further from the relative valve, to achievedifferent engine behaviour at various r.p.m.

The embodiments shown in FIGS. 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12,13, 14, 14A and 15A are therefore purely indicative and as such are notlimitative of the process. Said embodiments are therefore not to beconsidered as exhaustive of the possible internal and externalconfigurations of the multiple-section duct of the invention.

The invention can be implemented by any known technique and can also beapplied to ducts of already existing engines, and to suction orcompression machines.

What is claimed is:
 1. An intake and exhaust device with multiple sections of specific geometry for an internal combustion engine, for the purpose of optimizing the efficiency of said engine, the engine being of the type comprising at least one cylinder within which a piston moves, said cylinder receiving an air-fuel fresh gas mixture via an intake system or channel incorporating at least one relative usual intake valve, from said cylinder there emerging spent gas fed to an exhaust pipe via an exhaust system or channel, said channel incorporating at least one relative usual exhaust valve, said device comprising sectioning means located within one of said channels where said air-fuel gas mixture moves the improvement comprising wherein said sectioning means are structured and arranged for mounting either within the intake channel or the exhaust channel, the mounting being operated without any modification of said sectioning means, the sectioning means being fixed to the selected channel; said sectioning means structured and arranged to divide the channel where they are arranged into at least two ducts without modifying the length of the channel thereby allowing the retrofitting of said sectioning means to existing engines, said sectioning means structured and arranged to increase the transit velocity distribution of the gas flow through the channel by tending to make it uniform and speeding up the slowest gas thread by virtue of the dragging action generated on the slowest gas thread by the fastest gas threads, said sectioning means structured and arranged to maintain a turbulence level of said gas flow substantially constant, said sectioning means structured and arranged to modify the pressure and flow rate of the gas flow so as to improve cylinder filling and/or cylinder emptying, and wherein said sectioning means comprise at least an element through which the gas flows and which creates within said channel a first gas flow along said channel wall and at least a second gas flow which is directed substantially along the axis of said channel and wherein said element is at least one conical or frusto-conical element which is axially holed.
 2. A device as claimed in claim 1, wherein the sectioning means are carried internally by a body separate from the relative channel with which said means cooperate said body mounted within said channel.
 3. A device as claimed in claim 1, wherein the sectioning means form part of the channel within which they are positioned.
 4. A device as claimed in claim 1, wherein the sectioning means are associated with an annular support element associated with the channel within which they are positioned.
 5. A device as claimed in claim 4, wherein the annular support element is external to the channel and coaxial to the channel.
 6. A device as claimed in claim 1, wherein the conical or frusto-conical element tapers in the direction of the gas flow through the channel in which said element is positioned.
 7. A device as claimed in claim 1, wherein the conical or frusto-conical element tapers in the direction contrary to the direction of the gas flow through the channel in which said element is positioned.
 8. A device as claimed in claim 1, comprising at least two hollow frusto-conical elements positioned in succession within the channel through which the gas flow passes.
 9. An intake and exhaust device with multiple sections of specific geometry for an internal combustion engine, for the purpose of optimizing the efficiency of said engine, the engine being of the type comprising at least one cylinder within which a piston moves, said cylinder receiving an air-fuel fresh gas mixture via an intake system or channel incorporating at least one relative usual intake valve, from said cylinder there emerging spent gas fed to an exhaust pipe via an exhaust system or channel, said channel incorporating at least one relative usual exhaust valve, said device comprising sectioning means located within one of said channels where said air-fuel gas mixture moves the improvement comprising wherein said sectioning means are structured and arranged for mounting either within the intake channel or the exhaust channel the mounting being operated without any modification of said sectioning means, the sectioning means being fixed to the selected channel; said sectioning means are structured and arranged to divide the channel where they are arranged into at least two ducts without modifying the length of the channel thereby allowing the retrofitting of said sectioning means to existing engines, said sectioning means are structured and arranged to increase the transit velocity distribution of the gas flow through the channel by tending to make it uniform and speeding up the slowest gas thread by virtue of the dragging action generated on the slowest gas thread by the fastest gas threads, said sectioning means are structured and arranged to maintain a turbulence level of said gas flow substantially constant, said sectioning means are structured and arranged to modify the pressure and flow rate of the gas flow so as to improve cylinder filling and/or cylinder emptying and wherein the sectioning means modifying the section of the channel consist of at least one body having a cross-section whose dimensions vary in the direction of the gas flow passing through the relative channel.
 10. A device as claimed in claim 9, wherein the element of variable cross-section has parts converging towards and parts diverging from the axis of the channel wherein it is located.
 11. A device as claimed in claim 1, wherein the sectioning means are fixed within the system or channel in which they are positioned.
 12. An intake and exhaust device with multiple sections of specific geometry for an internal combustion engine, for the purpose of optimizing the efficiency of said engine, the engine being of the type comprising at least one cylinder within which a piston moves, said cylinder receiving an air-fuel fresh gas mixture via an intake system or channel incorporating at least one relative usual intake valve, from said cylinder there emerging spent gas fed to an exhaust pipe via an exhaust system or channel, said channel incorporating at least one relative usual exhaust valve, said device comprising sectioning means located within one of said channels where said air-fuel gas mixture moves the improvement comprising wherein said sectioning means are structured and arranged for mounting either within the intake channel or the exhaust channel, the mounting being operated without any modification of said sectioning means, the sectioning means being fixed to the selected channel; said sectioning means are structured and arranged to divide the channel where they are arranged into at least two ducts without modifying the length of the channel thereby allowing the retrofitting of said sectioning means to existing engines, said sectioning means are structured and arranged to increase the transit velocity distribution of the gas flow through the channel by tending to make it uniform and speeding up the slowest gas thread by virtue of the dragging action generated on the slowest gas thread by the fastest gas threads, said sectioning means are structured and arranged to maintain a turbulence level of said gas flow substantially constant, said sectioning means are structured and arranged to modify the pressure and flow rate of the gas flow so as to improve cylinder filling and/or cylinder emptying and wherein said sectioning means are mounted by mounting means, within said system or channel, for permitting the movement of the sectioning means within the system or channel in which they are mounted, either along the longitudinal axis of the system or channel or about it, said mounting means being an annular ring or sleeve structured and arranged to conform to the perimeter of the channel on which said sectioning means is integrally formed with said ring.
 13. A device as claimed in claim 12, wherein said movement of the sectioning means is controlled by actuator means for adjusting the position of said sectioning means, said actuator means responsive to the revolutions per minute of the engine so as to modify the relative position of the sectioning means within the corresponding system or channel along the longitudinal axis or about it in response to the revolutions per minute of the engine.
 14. A device as claimed in claim 1, wherein within the respective channel, the sectioning means define gas-flow transit sections which connected together by portions which are at least partially communicating.
 15. A device as claimed in claim 14, wherein the gas-flow transit sections have an entry area different from their exit area.
 16. An intake and exhaust device with multiple sections of specific geometry for an internal combustion engine, for the purpose of optimizing the efficiency of said engine, the engine being of the type comprising at least one cylinder within which a piston moves, said cylinder receiving an air-fuel fresh gas mixture via an intake system or channel incorporating at least one relative usual intake valve, from said cylinder there emerging spent gas fed to an exhaust pipe via an exhaust system or channel, said channel incorporating at least one relative usual exhaust valve, said device comprising sectioning means located within one of said channels where said air-fuel gas mixture moves the improvement comprising wherein said sectioning means are structured and arranged for mounting either within the intake channel or the exhaust channel, the mounting being operated without any modification of said sectioning means, the sectioning means being fixed to the selected channel; said sectioning means are structured and arranged to divide the channel where they are arranged into at least two ducts without modifying the length of the channel thereby allowing the retrofitting of said sectioning means to existing engines, said sectioning means are structured and arranged to increase the transit velocity distribution of the gas flow through the channel by tending to make it uniform and speeding up the slowest gas thread by virtue of the dragging action generated on the slowest gas thread by the fastest gas threads, said sectioning means are structured and arranged to maintain a turbulence level of said gas flow substantially constant, said sectioning means are structured and arranged to modify the pressure and flow rate of the gas flow so as to improve cylinder filling and/or cylinder emptying and wherein said sectioning means comprise at least an element through which the gas flows and which creates within said channel a first gas flow along said channel wall and at least a second gas flow which is directed substantially along the axis of said channel and wherein said element is at least one half-cone frustum element. 